Push bench



Oct. 29, 1940. v HEETKAMP 2,219,995

rusu BENCH Filed June 1, 1939 'w a s p L Z 9 -EYFIZ m I HEINRICH HEETKAMPQ BY HIS ATTORNEYS INVE NTOR Patented Oct. 29, 1940 UNITED STATES BUSH BENCH Heinrich Heetkamn, Butler-loll, Kreis Dusseldorf, Germany Application June 1, 1939, Serial No. 276,923 In. Germany May 2, 1938 1 Claim.

This invention relates to the manufacture of tubes and like articles.

More particularly the invention is concerned with the draw bench in a tube drawing machine,

5 and with reference to which it is hereinafter described as applied. I

In tube drawing machines both the stock rod and the mandrel must'be so supported and guided on the draw bench that they arenot subjected to bending stresses as the tube is being drawn, usually through a draw ring. For this purpose stationary shells or rollers have already been proposed, the rack for driving the stock rod being so arranged in relation thereto and so connected with it that in passage it will not obstruct the guiding elements which are stationary.

Other forms of guiding elements are known which for instance are capable of displacement so as not to interfere with the passage of the driving rack. In both kinds of guide it is however necessary for a part of the guide elements to be withdrawn'before a new mandrel can be inserted in the guides.

Up to the present no provision has been made for a simple means of adjustment of the draw bench to accommodate tubes of different sizes and when changing the stock rod and the mandrel for a particular size of tube the guide elements must also be changed which is a cumbersome and costly operation due to waste of time and interruption of work on the machine. Moreover a large number of sizes of guide elements haveto be kept in store for which the capital outlay is considerable.

The object of this invention is to provide a simple means of adjusting the guide elements which is eifected in situ on the draw bench and dispenses with the necessity of interchangeable guide parts.

In a draw bench for use with a tube or like drawing machine, the guide mechanism for the stock rod and mandrel comprises a series of grooved rollers arranged at spaced intervals beneath the stock rod and/or mandrel to support the same and co-operating with the rollers are a series of upper guide elements arranged in pairs for engagement with the upper side of the stock rod and/or mandrel and so as not to obstruct the driving rack, both the upper and lower guide 50 elements being capable of relative adjustment in order to accommodate varying sizes of stock rod and/ or mandrel, actuatingmeanscommon to the elements in each series being provided for effecting the necessary adjustment of the same.

55 In the preferred form of the invention the upper guiding elements take the form of two armed levers arranged outside the path of travel of the driving rack.

The invention is illustrated in the accompanying drawing, in which Figure 1 is a part sectional 5 elevation of the guide mechanism for a tube draw bench with the stock rod supported therein, and Figure 2 is a transverse sectional view of the same.

Figure 3 is a similar sectional view but showing 10 a stock rod of smaller size.

Referring to the drawing, (1 indicates a driving rack 'fast or integral with the underside of which is a stock holder b, and c is the stock rod which is fastened in to the end of the holder b. I 15 The stock rod 0 is supported throughout its length by a series of double coned or like grooved 'rollers d, which provide two points of support about its circumference, .the'rollers being mounted in a bed plate e, which as shown is conven- 20 iently U-shaped.. Co-operating with the supporting rollers is a series of guide elements J, spaced in pairs along the upper side of the stock rod, and so arranged as to permit the uninterrupted passage of the stockholder b.

Should it be desired to use a smaller diameter stock'rod than the rod 0 shown in Figure 2, the position of the rollers d and the upper guide elements require relative adjustment which is efiected preferably by raising the rollers d and at the same time by dropping the guide elements f.

For this purpose the guide elements I preferably take the form of two armed levers g mounted on pivots. k in slots m formed at intervals in the side walls 1 between which the stock rod is guided, the levers having their outer arms ar ranged to extend through the slots.

The guide elements of each series areadiusted by means common to each one, the particular guide mechanism of this invention lending itself to a very simple form of adjustment by a wedge or cam device. 5:

Extending beneath the bed pla e is a bar h,

at intervals along which corresponding to the uide rollers are ramps h, the plate e having depending lugs e"to engage' the ramps. Likewise extending beneath the outer arms of the levers g are bars i having. suitably spaced ramps i' for engagement with the lever the bars i being interconnected to move in unison.

Raising of the rollers d is obtained by longitudinal adjustment oi'. j tlie;bar h, the bed plate e being held against longitudinal displacement but.

left free to move up or down in its recess in the machine bed. Lowering of the guide elements I bet I for changing the stock rods is very simple. takes place by adjustment oi the bars i. the ramps i thereon citfising the levers a to rock about their pivots k.

When interchanging the stock rod and inserting a new mandrel in the guides. the guide elements. I are withdrawn sideways away from the stock rod and the mandrel, for which purpose the pivots k are mounted in'blocks p slidable within the slots m. The slides may be actuated in any suitable manner and are so arranged that the slides opposite the mandrel rod are associated as a group and movable as a unit.- The same applies to the slides which are withdrawn on interchange of the stock rods. It will be appreciated that adjustment of th guides oi the machine tor a stock rod and-a mandrel of larger or smaller diameter is a simple matter and can be carried out quickly and almost without labour expense, all that is required being adjustment of the wedge bars bymeans of any desired power mechanism, when all the rollers d are raised simultaneously and to the same extent. The same holds good for the guide elements I,

whose wedge elements i are interconnected ior' simultanous adjustment by any desired power means. Also the withdrawal of the guide mem- Only small masses need be moved.

While the invention has been described and illustrated as applied to a push bench for use .in a tube draw machine wherein the mandrel pushes the tube which is closed at one and through the draw ring or die, it will be understood that the invention is applicable to tube draw bench apparatus generally.

I claim;

Draw bench apparatus for use with tube or like drawing machines having a rack operated mandrel, comprising two series of upper guiding elements in the form of two armed levers arranged outside the path of travel o! the driving rack for the stock rod and mandrel and a series of lower guiding elements inthe form of double coned or like groovedrollers, the guiding elements in each series being capable of adjustment substantially radially with respect to the longitudinal axis of the stock rod and mandrel and actuating means for efiecting the simultaneous adjustment of the elements in each series, said actuating means comprising a bar having wedge or cam surfaces corresponding to the guiding elements to be adjusted.

. HEINRICH HEETKAMP. 

